The invention relates to a pneumatically actuated strapping apparatus for strapping a plastics tape around a package, including a motorized tensioning device and a motorized welding device for the plastics tape.
Apparatus of this type are known. The plastics tape is firstly placed in a loop around a package, wherein a first, free end forms at a welding point a bottom band. The other end of the plastics tape loop is guided as a top band, together with the bottom band, at a connecting point through the welding device, and subsequently runs to the tensioning device. In the tensioning device is then provided a friction wheel or a similar element, which is driven by a motor. This motorized friction wheel grips the top band and thereby tautens the loop around the package.
Once the plastics tape is then wound tightly around the package, it is compressed in this state at the place where it runs through the welding device. There, a vibrating plate, as part of the welding device, is then lowered onto the clamped-together bands and set in vibration. The vibration is generated by a motor via a gear mechanism. Due to this vibration, a relative movement ensues between the top and the bottom band, which, owing to the friction which is hereupon generated, leads to local fusion of the thermoweldable plastics tape. Following completion of the vibration movement and a short period of cooling, the top band and the bottom band are then welded together at the connecting point.
During the vibration or during the welding operation, respectively, the top band is usually cut off next to the connecting point. Finally, the strapping apparatus can then be removed from the package around which the plastics tape is wound.
Since strapping apparatus are used at a wide variety of locations and, due to different packages, also in a wide variety of positions, they are often handled manually and moved, for example, to their various usage sites. From this point of view, it is important that the apparatus creates minimal physical loads for a user.